ABSTRACT

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Most importantly for this chapter, OLED fabrication methods are dependent upon the properties of the substrate. Various approaches have been demonstrated for both vacuum thermal evaporation (see Chapter 14) and solution processing (see Chapter 15) of OLED materials and backplanes. e design of the fabrication process depends on the properties of the substrate. For instance, thermal cycling, as may be necessary during cleaning or deposition steps, can lead to substrate distortions, particularly if the coecient of thermal expansion (CTE) is high and cycling leads to distortion, as for polymer substrates. Generally speaking, glass substrates are used in batch processes and polymer substrates are used in either batch or roll-to-roll fabrication. Metal foils are oen demonstrated using batch-processing methods, but can conceivably be utilized in a roll-to-roll process. However, exible glass has been introduced which can also be used in either conguration, as will be discussed later in this chapter. Finally, products may require that substrates demonstrate low weight, exibility, thin form factor, low cost, or other characteristics important to consumers.